Leo initially fought ‘The Fighter’

Thesp had doubts about portraying Wahlberg's mom

Says Melissa Leo of taking on “The Fighter”: “I’ve never gone into something doubting so much.”

While the veteran actress was both eager to work with director David O. Russell and intrigued by the true story of the improbable rise of boxing champ Micky Ward, she wasn’t sure if, at age 50, she could pull off playing mom to screen son Mark Wahlberg, 39, not to mention eight other grown children.

And then there was her character’s distinct hairstyle — close-cropped, frosted-to-the-hilt look that the real Alice Ward sported in the ’80s.

“I doubted that it would work on me,” says the redheaded Leo, “but David kept saying, ‘Cut it shorter! Go lighter! Lighter!’ I just hoped all the doubt would vanish when the cameras rolled.”

She needn’t have worried. True, in less-skilled hands, the take-no-prisoners Alice who, as her son’s manager, hinders Micky’s career almost as much as she helps, could’ve easily been a caricature. Yet beneath the loud leopard-print-clad exterior, Leo creates a complex portrait of a working-class woman who’ll do whatever it takes to hold her troubled family together.

“I felt empathy for her,” says the actress, who spent quality time with the real Alice while shooting on location in Lowell, Mass. “The mother’s lot in life is the greatest joy and the hardest water to tread. Her biggest impediment in a remarkable life has been the hugeness of her heart. She loves hard, and she is loved hard.”

Managing to fit the project in was a challenge for the increasingly busy Leo, who’s not only a series regular on HBO’s “Treme” but has also appeared onscreen this year in “Welcome to the Rileys” and “Conviction.” In the end, though, she’s grateful her initial doubts didn’t keep her away from “The Fighter.”